Slide 1: BIRD1 Cohort 1 Baseline Demographics and Key Endpoints for IRDs
BIRD1 Cohort 1 Baseline Demographics and Key Endpoints for IRDs A Phase 1b/2a, Open-Label, Dose-Exploration Basket Study to Investigate the Safety and Tolerability of Subretinally Injected OPGx-BEST1 Administered in Patients With Either Autosomal-Dominant BEST1 Disease (Best Vitelliform Macular Dyst
Slide 2: Disclosures and Forward-Looking Statements
Disclosures and Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements include, but are not limited to, statements concerning data from and future enrollment for our clinical trials
Slide 3: Study Design
5/13/26 Study Design • Phase 1b/2a open-label, dose-exploration Study Visit Schedule safety and tolerability study Visit 1 Screening, BL1, and Screening BL2 within 90 days • N=5 (Cohort 1) Visit 2 before IMP admin Baseline 1 At least 3 days prior to • Subretinal injection of OPGx-BEST1 in one Visit
Slide 4: Baseline Participant Demographics
Baseline Participant Demographics Participant # 101-101 101-104 102-101 102-102 101-106 Age 63 59 50 45 31 Sex Female Female Male Male Male BEST ARB ARB BVMD BVMD BVMD phenotype/mutation Study (treated) eye* OS OD OS OS OS Baseline VA 1.68 0.7 0.72 0.49 0.77 (study/treated eye) Baseline VA 0.84 0.41
Slide 5: 101-101 (ARB): Baseline OCT
101-101 (ARB): Baseline OCT Study Eye (Treated Area) Study Eye (Untreated Area) 5 OCT, optical coherence tomography.
Slide 6: 101-104 (ARB): Baseline OCT
101-104 (ARB): Baseline OCT Study Eye (Treated) Fellow Eye (Untreated) 6 OCT, optical coherence tomography.
Slide 7: 101-104 (ARB): Baseline Microperimetry
101-104 (ARB): Baseline Microperimetry Sensitivity Map Fixation Plot Average Threshold Study Eye (Treated) Fellow Eye (Untreated) 7
Slide 8: 102-101 (BVMD): Baseline OCT
102-101 (BVMD): Baseline OCT Study Eye (Treated) Fellow Eye (Untreated) 8 OCT, optical coherence tomography.
Slide 9: 102-101 (BVMD): Baseline Microperimetry
102-101 (BVMD): Baseline Microperimetry Sensitivity Map Fixation Plot Average Threshold Study Eye (Treated) Fellow Eye (Untreated) 9
Slide 10: 102-102 (BVMD): Baseline OCT
102-102 (BVMD): Baseline OCT Study Eye (Treated) Fellow Eye (Untreated) 10 OCT, optical coherence tomography.
Slide 11: 102-102 (BVMD): Baseline Microperimetry
102-102 (BVMD): Baseline Microperimetry Sensitivity Map Fixation Plot Average Threshold Study Eye (Treated) Fellow Eye (Untreated) 11
Slide 12: 101-106 (BVMD): Baseline OCT
101-106 (BVMD): Baseline OCT Study Eye (Treated) Fellow Eye (Untreated) 12 OCT, optical coherence tomography.
Slide 13: 101-106 (BVMD): Baseline Microperimetry
101-106 (BVMD): Baseline Microperimetry Sensitivity Map Fixation Plot Average Threshold Study Eye (Treated) Fellow Eye (Untreated) 13
Slide 14: Overview of Study Endpoints
Overview of Study Endpoints 1 Best-corrected visual acuity (BCVA) 2 Low-luminance visual acuity (LLVA) 3 Contrast Sensitivity 4 Optical coherence tomography (OCT) 5 Microperimetry 14
Slide 15: Visual Acuity Testing
Visual Acuity Testing B C VA L LVA • Ability to see in low-light or dim • Assessment for Clarity of Vision conditions Description • Determines the smallest object that can • Enables earlier detection of disease be seen at a specified distance changes • Measured using ETDRS letter charts with a 2.0 l
Slide 16: ETDRS Testing Using the Good Lite System
ETDRS testing using the Good Lite System allows LogMAR acuity testing in Low Vision Patients Standard ETDRS Good-Lite Low Vision • Measures up to LogMAR 2.7 in 0.1 increments • Same illuminator cabinet as standard ETDRS Chart • Closest test distance is equivalent to BRVT at 0.25M • No requirement to
Slide 17: LLVA Is More Sensitive than BCVA for Detecting Foveal Dysfunction
LLVA is More Sensitive than BCVA for Detecting Foveal Dysfunction LLVA is measured by testing a patient’s ability to read a standard ETDRS chart while wearing a 2.0 log unit neutral density filter over their eye, which reduces standard room lighting ~100 fold “LLVA has been shown to be more effectiv
Slide 18: Contrast Sensitivity Testing Is More Sensitive to Impairment than BCVA
Contrast Sensitivity Testing is More Sensitive to Impairment than BCVA • Ability of the visual system to detect differences in photometric Description brightness in the visual field1 à How much contrast is needed to see targets with different spatial details2 • Contrast sensitivity function is deriv
Slide 19: EZ Loss and ONL Thinning Correlate with VA Loss
EZ Loss and ONL Thinning Correlate with VA Loss • Ellipsoid zone (EZ) is the hyperreflective band and represents inner segments of photoreceptors • Measures the structural integrity of the photoreceptors • Presence and thickness correlates directly with VA and disease stage • EZ loss typically found
Slide 20: OCT Imaging
OCT Imaging High-resolution cross-sectional images of retinal BVMD Stages Description Fundus OCT layers à Structural endpoint of anatomical changes Stage 1: • SD-OCT is used to acquire scans of the retina along Pre-vitelliform with an infrared fundus image, which allows the scan to be oriented in re
Slide 21: CST Does Not Capture Changes Outside the Central Subfield
CST Does Not Capture Changes Outside the Central Subfield 6 mm Outer ring: Four peri-foveal subfields 3 mm Inner ring: Four para-foveal subfields 1 mm Central circle: Central subfield (fovea) Changes Changesin inthickness thicknessoutside outsidecentral central subfield subfieldwill will not notbe b
Slide 22: Microperimetry Allows Targeted Testing of Retinal Sensitivity
Microperimetry Allows Targeted Testing of Retinal Sensitivity • Produces a sensitivity map of the retina Description • Evaluates the ability to perceive light stimuli at pre-specified retinal locations with focus on the central part of the retina • Stimuli are presented at a mesopic background lumin
Slide 23: Microperimetry of BVMD Lesion Types
Microperimetry of BVMD Lesion Types • Vitelliform: Subretinal hyperreflective material with good macular sensitivity thresholds • Mixed: Presence of both subretinal hyperreflective material and fluid, but with no decay in sensitivity thresholds • Subretinal fluid: Complete reabsorption of subretinal
Slide 24: Thank You
Thank you! OPUS eae N E gine Sy